"John?"

He woke suddenly. It was almost as though John had been trained to wake the second he heard Sherlock's voice. Rubbing his face, he sat up in bed, searching for the source of the voice. A tall, lean silhouette was stood just to the right of the door.

"Sherlock? What is it?" he asked.

"Oh!" Sherlock said. If John had been more alert, he probably would have sensed a mildly embarrassed inflection in his voice. "Nothing, I wanted to know whether you were awake or not."

John rubbed his face again, becoming slightly more aware of his surroundings; the fog of sleepiness was very slowly lifting. "Well, I am now. What was it?"

"I... can't sleep." Sherlock stated slowly.

Somewhere in the back of Johns mind he knew the truth. Sherlock never tried to sleep. He would sleep when he needed it. Slight insomnia, John was sure, would never really affect him.

"Nightmares?" John asked, without thinking. He knew that Sherlock suffered from nightmares. Sometimes, he would wake from his sleep with a shriek that would ring through the entire flat. It made John feel sick to hear. Sherlock had seen so many things, yet it was only sleep that told John that his best friend had a true fear of something.

Once, Sherlock had fallen asleep on the sofa. John noticed his constant flinches and the look of pure terror drawn across his sleeping face. It affected John more than he consciously realised. Sherlock always seemed fearless, so whatever had been haunting his dreams, John thought, was surely horrific.

Johns question was answered with no reply. A yawn overcame John, reminding him of the deep sleep he had just been woken from. The rest, John doesn't remember. All he knows is that the next morning, Sherlock's slender arm was resting on his hip. Sherlock's breath was tickling the hairs on the back of his neck and sending shivers down his spine. Sherlock's knee was resting against the back of his own leg.

He edged out of the bed, so as not to wake his friend. He looked at Sherlock's face. Not flinching. Not looking the slightest bit scared. He looked content. Safe. It made John happy.

John realised that he didn't really want to be out of bed, after all. He wanted to be curled back in bed, sleeping next to a man who had no concept of "personal space".

Smiling to himself, he promised that if it should ever happen again, he would stay a little longer.

The next evening, John really couldn't sleep. He was preoccupied, listening for any signs of Sherlock being awake. There was nothing. He wasn't even sure whether Sherlock would actually be trying to sleep at all. His sleeping habits were sporadic at best. Curiosity finally getting the best of him, John got out of bed, and made his way to the downstairs of 221b. He could see the lights of the living room turned off and a tiny sliver of light was coming from the gap between Sherlock's bedroom door and the hallway. It didn't take the deductive powers of Sherlock Holmes to know where he was. After a moment of hesitation, John slowly pushed open Sherlock's bedroom door.

Sherlock was in sat up in bed, using his laptop, the bluish light illuminating his face and making him look paler than he already was. John noted how... alien... it made him look. John also couldn't help noticing that Sherlock's chest was exposed. As far as John could tell, Sherlock was naked. John could feel his cheeks reddening at the sight.

Sherlock raised a questioning eyebrow. John shrugged, his heart pounding. "Can't sleep. Mind if I join you?"

Sherlock smiled, "no. It's the least I can do," he said, moving from the middle of the bed to the left side. This movement exposed Sherlock's legs, and John noticed that Sherlock was in fact wearing pyjama bottoms. A slight giggle overcame him. As if I was preparing to get in bed with a naked Sherlock! He thought to himself.

Sherlock appeared to be aware of John's train of thought and smiled too. John got into the bed. He was used to sleeping on the left, not the right. And he certainly wasn't used to his sheets smelling so much like Sherlock. It was strange, but John honestly couldn't say it was unpleasant.

"You know about the nightmares" Sherlock stated, closing his laptop, and placing it on the bedside table. The room was now completely dark. John felt the change in the mattress springs as Sherlock lay down on the bed.

"I've heard you shout when you're asleep. And..." John hesitated. His instincts were telling him that it would be a difficult subject for Sherlock. He'd never seen any other sign of true weakness in his friend before. "And... whenever I've seen you sleep, you always look... terrified."

Sherlock didn't respond. John began to wonder whether he'd outstayed his welcome. He began to wonder which would be less awkward- to stay or to leave. Mid way through his thoughts on the subject, Sherlock finally replied.

"My Father," he stated quietly.

"What?" John asked with a start.

My Father. He wasn't a particularly nice man," Sherlock sighed. "He... had a short temper; prone to lashing out. I was sixteen years old. I walked in on my Father as he was about to attack my Mother. It made me so... angry." Sherlock's voice wavered slightly. He took a deep breath and continued. "I didn't know what to do. I couldn't talk to my Mother about it, and Mycroft was at Uni. I wanted to hurt him and it was the only thing I could think of. I worked out that been having an affair. I'd known it for weeks. So, when I was alone with him, I told him. I suppose I planned on blackmailing him. It was probably one of the stupidest things I'd done in my life. He lost his temper, almost hospitalised me, and told me not to come home." Sherlock stopped speaking, and John's brain thinking through the scenario.

How could someone do that to their child? To their wife? It made him feel sick. "Jesus. And you... You dream about it?" John asked knowing the answer already.

"Yes" Sherlock said. The image of a sixteen year old Sherlock being beaten to a pulp couldn't get out of Johns mind, and he wondered whether he'd ever be able to sleep again.

Sherlock coughed into the darkness, "but I was fine last night. And I think I'll be fine tonight."